Systems and Methods For Dewatering Mine Tailings With Water-Absorbing Polymers

ABSTRACT

Systems and methods for dewatering mine tailings with water-absorbing polymers. The systems and methods may include combining a mine tailings slurry, which includes mine tailings and water, with a water-absorbing polymer. The water-absorbing polymer may absorb water from the mine tailings, thereby increasing a solids content of the mine tailings. The mine tailings may be combined with the water-absorbing polymer prior to, during, and/or subsequent to transfer of the mine tailings to a mine tailings dewatering and/or disposal site. In some embodiments, the water-absorbing polymer may be an encapsulated water-absorbing polymer.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the priority benefit of Canadian PatentApplication 2,812,271 filed Apr. 10, 2013 entitled SYSTEMS AND METHODSFOR DEWATERING MINE TAILINGS WITH WATER-ABSORBING POLYMERS, the entiretyof which is incorporated by reference herein.

FIELD OF THE DISCLOSURE

The present disclosure is directed to systems and methods for dewateringmine tailings with water-absorbing polymers.

BACKGROUND OF THE DISCLOSURE

Mining operations, including mining operations that remove bitumen fromoil sands, generate a waste stream that may be referred to generally asmine tailings. These mine tailings often may include a significantquantity of water and may be stored in a storage facility, or structure,such as an enclosure, or pond. Over time, particles within the storedmine tailings may settle, producing a relatively stable suspension ofthe particles in the water that may have a solids content ofapproximately 30 wt %. This suspension may be referred to herein asmature fine tailings (MFT) and has a very low shear strength. Thus, theMFT cannot be built upon and vegetation often may not grow thereon.

Because of the long dewatering time for the MFT and the high rate atwhich mine tailings may be generated, large volumes of mine tailingshave been, and continue to be, generated in various parts of the world.Environmental concerns, space constraints, and/or government regulationsmay dictate that these mine tailings be processed to a more stable form,thereby permitting reclamation of the storage facility, revegetation ofthe mine tailings, and/or further/other use of the storage facility. Asan illustrative, non-exclusive example, Canadian Directive 74 requiresthat stored mine tailings be processed such that they have a shearstrength of at least 5 kilopascals (kPa) within one year of storage anda shear strength of at least 10 kPa within 5 years of storage. Meetingthis directive, for example, may require dewatering of the stored minetailings at a rate that is significantly higher than the dewateringrates that are experienced when the mine tailings are simply placed inthe storage facility and allowed to dewater naturally.

Several technologies have been developed that may increase thedewatering rate of the stored mine tailings; however, these technologiesoften are costly to implement, require large amounts of space, and/orare ineffective at reaching a target shear strength within a desiredperiod of time, such as to keep up with the rate at which additionalmine tailings are being generated and/or to meet the governmentregulations. Thus, there exists a need for improved systems and methodsfor dewatering mine tailings.

SUMMARY OF THE DISCLOSURE

Systems and methods for dewatering mine tailings with water-absorbingpolymers. In some embodiments, the systems and methods may includecombining a mine tailings slurry, which includes mine tailings andwater, with a water-absorbing polymer. In some embodiments, thecombining includes combining the mine tailings slurry with thewater-absorbing polymer to produce an augmented mine tailings slurry.

The mine tailings may be combined with the water-absorbing polymer priorto, during, and/or subsequent to transfer of the mine tailings to a minetailings dewatering site and/or to a mine tailings disposal site. Insome embodiments, the combining includes combining the mine tailingsslurry with the water-absorbing polymer within a mixing vessel, such asa thickening assembly. In some embodiments the combining includescombining the mine tailings slurry with the water-absorbing polymerwithin a transfer pipe. In some embodiments, the combining includescombining the mine tailings slurry with the water-absorbing polymer atthe mine tailings dewatering site.

In some embodiments, the systems and methods include piping theaugmented mine tailings slurry to the mine tailings dewatering site anddistributing the augmented mine tailings slurry within the mine tailingsdewatering site. In some embodiments, the systems and methods furtherinclude initiating water absorption by the water-absorbing polymersubsequent to the piping.

In some embodiments, the systems and methods include distributing themine tailings slurry within the mine tailings dewatering site andmechanically incorporating the water-absorbing polymer into the minetailings. In some embodiments, the systems and methods include waitingat least a threshold settling time subsequent to distributing the minetailings within the mine tailings dewatering site and prior to themechanically incorporating.

In some embodiments, the systems and methods include absorbing waterfrom the mine tailings with the water-absorbing polymer to generate aswollen water-absorbing polymer and a dewatered mine tailings slurry. Insome embodiments, the systems and methods further include reusing,recycling, and/or reclaiming at least a portion of the water-absorbingpolymer by separating the swollen water-absorbing polymer from thedewatered mine tailings slurry. In some embodiments, the systems andmethods further may include reclaiming at least a portion of the waterfrom the swollen water-absorbing polymer and optionally may includereusing and/or recycling at least a portion of the reclaimed water.

In some embodiments, the water-absorbing polymer may be encapsulated ina coating material to form an encapsulated water-absorbing polymer. Thecoating material, when utilized, fluidly isolates the water-absorbingpolymer from the water that is contained within the mine tailings slurryfor at least a threshold isolation time subsequent to fluid contactbetween the water and the encapsulated water-absorbing polymer. In somesuch embodiments, the systems and methods may include selecting thecoating material and/or a thickness of the coating material thatencapsulates the water-absorbing polymer, such as to regulate, ordefine, the threshold isolation time. In some embodiments, the selectingadditionally or alternatively includes selecting such that a ratio of adensity of the encapsulated water-absorbing polymer to a density of themine tailings slurry is less than a threshold value, or a thresholddensity ratio.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of illustrative, non-exclusiveexamples of mining operations that may include and/or utilize thesystems and methods according to the present disclosure.

FIG. 2 is a flowchart depicting methods according to the presentdisclosure of dewatering mine tailings.

FIG. 3 is a flowchart depicting additional methods according to thepresent disclosure of dewatering mine tailings.

FIG. 4 is a flowchart depicting methods of forming an encapsulatedwater-absorbing polymer according to the present disclosure.

FIG. 5 is a flowchart depicting methods according to the presentdisclosure of reclaiming, reusing, and/or recycling a water-absorbingpolymer.

DETAILED DESCRIPTION AND BEST MODE OF THE DISCLOSURE

FIG. 1 is a schematic representation of illustrative, non-exclusiveexamples of mining operations 20 that may include and/or utilize thesystems and/or methods according to the present disclosure. FIG. 1illustrates several options, variations, and/or embodiments of miningoperation 20, and it is within the scope of the present disclosure thata particular mining operation 20 may include, or may not include, any ofthe structures, streams, and/or materials that are illustrated inFIG. 1. It is further within the scope of the present disclosure that aparticular mining operation also may include one or more otherstructures, streams, and/or materials.

In some embodiments, mining operation 20 may include and/or be inmaterial communication with (i.e., may be configured to provide,receive, and/or exchange one or more material streams with) a minetailings generation site 30, which in turn is in material communicationwith a mine tailings dewatering system, or facility, 31. The minetailings generation site may be configured to generate a mine tailingsslurry 40 that includes mine tailings 42 and water 44, and this slurrymay be pumped, flowed, or otherwise transported or delivered to minetailings dewatering system 31 to remove at least a portion of the watertherefrom.

Mine tailings dewatering system 31 may include at least one mixingvessel 50 that is configured to add one or more additives to the minetailings slurry, such as to assist in or otherwise promote thedewatering process. For example, mine tailings slurry 40 may be suppliedto a mixing vessel 50, which may include and/or be a thickening assembly52. The mixing vessel also may receive a flocculant 58. Flocculant 58,when utilized, may be referred to herein as, and/or may be, a flocculantstream 58, and may be received by the mixing vessel from a flocculantsupply system 34. The mixing vessel further may receive awater-absorbing polymer 60 and/or an encapsulated water-absorbingpolymer 65 from a water-absorbing polymer supply system 32.Water-absorbing polymer 60 also may be referred to herein as, and/or maybe, a water-absorbing polymer stream 60. Encapsulated water-absorbingpolymer 65 includes water-absorbing polymer 60 that is encapsulated in acoating material 64. Accordingly, encapsulated water-absorbing polymer65 also may be referred to herein as, and/or may be, an encapsulatedwater-absorbing polymer stream 65.

When utilized in a particular mine tailings dewatering system 31 thatfurther utilizes both flocculant 58 and water-absorbing polymer 60(and/or an encapsulated water-absorbing polymer 65), the mixing vesselmay combine the mine tailings slurry, the flocculant, and thewater-absorbing polymer within an internal volume 51 thereof. The mixingvessel then may generate, or produce, an underflow 56, which also may bereferred to herein as, and/or may be, an underflow stream 56, a highsolids content stream 56, and/or an augmented mine tailings slurry 46.The mixing vessel also may generate, or produce, an overflow 54, whichalso may be referred to herein as, and/or may be, an overflow stream 54and/or a low solids content stream 54. Overflow 54 may be separate from,may be spaced apart from, and/or may include a different compositionthan underflow 56. As an illustrative, non-exclusive example, underflow56 may include a greater solids content than a solids content ofoverflow 54. As another illustrative, non-exclusive example, overflow 54may include a greater liquid content than a liquid content of underflow56.

Underflow 56 may be conveyed, pumped, and/or piped, such as through apipe 70, to a mine tailings dewatering site 80, where it may form a minetailings deposit 82. In such an embodiment, and as discussed herein,water-absorbing polymer 60 (and/or encapsulated water-absorbing polymer65) may be selected such that it may initiate absorption of water fromunderflow 56, thereby decreasing a water content of mine tailings 42that are contained therein (or at least partially dewatering the minetailings slurry), subsequent to formation of mine tailings deposit 82within mine tailings dewatering site 80.

Alternatively, and prior to being conveyed to the mine tailingsdewatering site, the underflow optionally may be provided to aseparation assembly 90. Water-absorbing polymer 60 may absorb water fromunderflow 56 within and/or prior to delivery to separation assembly 90to produce dewatered mine tailings slurry 92 and swollen water-absorbingpolymer 94. Separation assembly 90 may remove or otherwise separatedewatered mine tailings slurry 92 from swollen water-absorbing polymer94. Dewatered mine tailings slurry 92 optionally may be provided to minetailings dewatering site 80, such as by being trucked, pumped, piped,and/or otherwise conveyed to the mine tailings dewatering site, and mayform mine tailings deposit 82 therein.

In addition, and while not required in all embodiments, swollenwater-absorbing polymer 94 that is separated from the underflow may beprovided to water-absorbing polymer recycle system 62. Thewater-absorbing polymer recycle system may include a polymer dryingassembly 66, which may be configured to remove water from, release waterfrom, and/or dewater, the swollen water-absorbing polymer and to producewater-absorbing polymer 60, which also may be referred to herein asregenerated water-absorbing polymer 60. Water-absorbing polymer 60 thenmay be provided to a polymer coating assembly 68, which may coat,encapsulate, and/or otherwise cover water-absorbing polymer 60 withcoating material 64 to produce encapsulated water-absorbing polymer 65.As illustrated, water-absorbing polymer 60 (which may be included inencapsulated water-absorbing polymer 65, when present) then may bedischarged from water-absorbing polymer recycle system 62 and provided,or recycled, to another component of mining operation 20, such as towater-absorbing polymer supply system 32 and/or to mixing vessel 50.

Drying assembly 66 also may produce released water 67, which may bereferred to herein as released water stream 67. Released water 67 may bedischarged from the drying assembly separately from water-absorbingpolymer 60 and optionally may be recycled to another component of miningoperation 20, such as to mine tailings generation site 30.

Additionally or alternatively, and in other embodiments, miningoperation 20 may not include mixing vessel 50, water-absorbing polymer60 may not be provided to internal volume 51 of mixing vessel 50, and/orit may be desirable to combine an additional volume of water-absorbingpolymer 60 with underflow 56 and/or with augmented mine tailings slurry46. Under these conditions, mine tailings slurry 40, underflow 56 thatmay or may not include water-absorbing polymer 60 but includes minetailings 42 and water 44, and/or augmented mine tailings slurry 46 maybe conveyed via pipe 70 to mine tailings dewatering site 80. Pipe 70 mayinclude an injection port 72 that may be configured to receivewater-absorbing polymer 60 such that water-absorbing polymer 60 mixeswith mine tailings slurry 40 within pipe 70 to produce augmented minetailings slurry 46 (or to combine additional water-absorbing polymer 60with augmented mine tailings slurry 46).

Augmented mine tailings slurry 46 then may be provided to mine tailingsdewatering site 80. Subsequent to augmented mine tailings slurry 46being provided to mine tailings dewatering site 80, water-absorbingpolymer 60 may absorb water 44 from the augmented mine tailings slurry,thereby decreasing a water content of mine tailings 42 that arecontained therein (or at least partially dewatering mine tailings slurry40).

Additionally or alternatively, the augmented mine tailings slurry alsomay optionally be provided to separation assembly 90 prior to beingprovided to mine tailings dewatering site 80. Separation assembly 90 mayseparate the augmented mine tailings slurry into dewatered mine tailingsslurry 92 and swollen water-absorbing polymer 94, with dewatered minetailings slurry 92 subsequently being provided to mine tailingsdewatering site 80, as discussed herein. In addition, and as alsodiscussed, swollen water-absorbing polymer 94 optionally may be providedto polymer drying assembly 66 and/or polymer coating assembly 68 ofwater-absorbing polymer recycle system 62 to produce water-absorbingpolymer 60 and/or encapsulated water-absorbing polymer 65, which thenmay be provided to another component of mining operation 20, such as toinjection port 72.

In other embodiments, mine tailings slurry 40 and water-absorbingpolymer 60 (and/or encapsulated water-absorbing polymer 65) may beprovided directly to separation assembly 90. As discussed, thewater-absorbing polymer may absorb water from the mine tailings slurrywithin the separation assembly to produce dewatered mine tailings slurry92 and swollen water-absorbing polymer 94, which may be separatelydischarged from the separation assembly after removal, or separation, ofthe swollen water-absorbing polymer from the dewatered mine tailingsslurry 92. Subsequently, dewatered mine tailings slurry 92 may beprovided to mine tailings dewatering site 80. Furthermore, swollenwater-absorbing polymer 94 optionally may be provided to polymer dryingassembly 66 and/or polymer coating assembly 68 of water-absorbingpolymer recycle system 62 to produce water-absorbing polymer 60 and/orencapsulated water-absorbing polymer 65, which then may be provided toanother component of mining operation 20, such as to separation assembly90.

Additionally or alternatively, and in other embodiments, mine tailingsslurry 40 and water-absorbing polymer 60 (and/or encapsulatedwater-absorbing polymer 65) may be provided directly to mine tailingsdewatering site 80. As an illustrative, non-exclusive example, and asdiscussed herein with reference to methods 200, mine tailings 42 withinmine tailings slurry 40 and water-absorbing polymer 60 both may bedistributed and/or otherwise located within mine tailings dewateringsite 80. Subsequently, one or more mechanical incorporation devices 84may be utilized to mechanically incorporate, or mix, water-absorbingpolymer 60 into mine tailings 42. The water-absorbing polymer then mayabsorb water 44 from the mine tailings slurry, thereby decreasing awater content thereof. Illustrative, non-exclusive examples ofmechanical incorporation devices 84 include any suitable tractor,all-terrain vehicle, injector, rototiller, disk, and/or plow.

As discussed, it is within the scope of the present disclosure thatmining operation 20 and/or mine tailings dewatering system 31 mayinclude any suitable combination of the structures and/or may utilizeany combination of the methods that are disclosed herein. Additionallyor alternatively, it also within the scope of the present disclosurethat mining operation 20 further may include additional structuresand/or may utilize additional methods that may be known to conventionalmining operations 20 but that are not discussed in detail herein, andmine tailings dewatering system 31 further may include additionalstructures and/or may utilize additional methods that may be known toconventional mine tailings dewatering systems but that are not discussedin detail herein. Similarly, the structures, streams, and/or materialsdisclosed herein may take, include, and/or define any suitable formand/or function, illustrative, non-exclusive examples of which arediscussed herein.

With this in mind, mine tailings generation site 30 may include anysuitable mine and/or mining operation that may produce mine tailingsslurry 40. As illustrative, non-exclusive examples, this may include anysuitable oil sands mine and/or tar sands mine. In addition, minetailings generation site 30 may generate, or produce, mine tailingsslurry 40 in any suitable manner. As an illustrative, non-exclusiveexample, mine tailings generation site 30 may include a mining operationthat may utilize hot water extraction technology to liberate bitumenfrom finely crushed bitumen-containing ore. This may include combining,or mixing, the bitumen-containing ore with hot water and/or one or moredispersion agents to separate the bitumen from a remainder of thebitumen-containing ore.

Mine tailings slurry 40 may include and/or be any suitable slurry thatmay be generated by mine tailings generation site 30 and that includesmine tailings 42 and water 44. As an illustrative, non-exclusiveexample, the above-described bitumen separation process may produce abitumen-containing, or bitumen-rich, stream (i.e., a product stream) anda waste stream. The waste stream may contain a large number of smallparticles (i.e., particles with a size of less than a few micrometers,such as clays) suspended in water. Typically, the waste stream mayinclude 30-60 wt % water, and it may be desirable to remove at least aportion of this water from the mine tailings slurry, such as by usingthe systems and/or methods disclosed herein. It is within the scope ofthe present disclosure that mine tailings slurry 40 may include, and/orbe, the above-described waste stream. However, it is also within thescope of the present disclosure that the waste stream may receivefurther processing prior to being utilized within mining operation 20 asmine tailings slurry 40. Thus, mine tailings slurry 40 also may includeand/or be any suitable oil sands tailings, thickened tailings (TT),mature fine tailings (MFT), solvent recovery unit tailings (TSRU),flotation tailings (FT), and/or fluid fine tailings (FFT).

As discussed, mine tailings slurry 40 may include, and/or be, a wastestream from a bitumen recovery process. As such, it is within the scopeof the present disclosure that the mine tailings slurry further mayinclude bitumen. As illustrative, non-exclusive examples, mine tailingsslurry 40 may include at least 0.005 wt % bitumen, at least 0.01 wt %bitumen, at least 0.05 wt % bitumen, at least 0.1 wt % bitumen, at least0.5 wt %, at least 1 wt %, at least 2 wt %, at least 3 wt %, at least 4wt %, at least 5 wt %, or at least 6 wt % bitumen. As additionalillustrative, non-exclusive examples, the mine tailings slurry mayinclude less than 15 wt %, less than 14 wt %, less than 13 wt %, lessthan 12 wt %, less than 11 wt %, less than 10 wt %, less than 9 wt %,less than 8 wt %, less than 7 wt %, less than 6 wt %, less than 5 wt %bitumen, less than 4 wt % bitumen, less than 3 wt % bitumen, less than 2wt % bitumen, less than 1 wt % bitumen, or less than 0.5 wt % bitumen.

Mine tailings slurry 40 may include small particles (i.e., particleswith a size, or diameter, of less than 44 micrometers), and it is withinthe scope of the present disclosure that the mine tailings slurry alsomay include larger particles (i.e., particles with a size, or diameter,of greater than 44 micrometers, such as sand). When mine tailings slurry40 includes both small particles and sand, a sand-to-fines ratio of themine tailings slurry may define any suitable value. As illustrative,non-exclusive examples, the sand-to-fines ratio may be less than 4:1,less than 3:1, less than 2:1, less than 1:1, less than 1:1.2, less than1:2, less than 1:3, less than 1:4, less than 1:5: or less than 1:6.Additionally or alternatively, the sand-to-fines ratio also may be atleast 1:15, at least 1:14, at least 1:13, at least 1:12, at least 1:11,at least 1:10, at least 1:9, at least 1:8, at least 1:7, at least 1:6,at least 1:5, at least 1:4, at least 1:3, at least 1:2, at least 1:1.1,or at least 1:1.

Water-absorbing polymer 60 may include any suitable material that maydefine any suitable form. In addition, water-absorbing polymer 60 may bepresent within underflow 56 (or augmented mine tailings slurry 46),separation assembly 90, mine tailings disposal site 80, and/or minetailings deposit 82 in any suitable concentration. As illustrative,non-exclusive examples, a concentration (in weight percent of solids orweight percent on a dry mass basis) of water-absorbing polymer 60relative to mine tailings 42 may be at least 0.00001 wt %, at least0.00005 wt %, at least 0.0001 wt %, at least 0.0005 wt %, at least 0.001wt %, at least 0.005 wt %, at least 0.01 wt %, at least 0.05 wt %, atleast 0.1 wt %, at least 0.5 wt %, or at least 1 wt %. Additionally oralternatively, the concentration of the water-absorbing polymer may beless than 5 wt %, less than 4.5 wt %, less than 4 wt %, less than 3.5 wt%, less than 3 wt %, less than 2.5 wt %, less than 2 wt %, less than 1.5wt %, less than 1 wt %, less than 0.5 wt %, less than 0.1 wt %, lessthan 0.05 wt %, or less than 0.01 wt %.

As another illustrative, non-exclusive example, a material thatcomprises water-absorbing polymer 60 may be selected such that thewater-absorbing polymer will absorb at least a threshold mass of waterper gram (or gram on a dry weight basis) of the water-absorbing polymer.This may include absorbing at least 1 gram (g), at least 5 g, at least10 g, at least 50 g, at least 100 g, at least 200 g, at least 300 g, atleast 400 g, at least 500 g, at least 1,000 g, or at least 5,000 g ofwater per gram of water-absorbing polymer. Additionally oralternatively, this may include absorbing less than 20,000 g, less than15,000 g, less than 10,000 g, less than 7,500 g, less than 5,000 g, lessthan 2,500 g, less than 1,000 g, less than 750 g, less than 500 g, orless than 400 g of water per gram of water-absorbing polymer.

Illustrative, non-exclusive examples of water-absorbing polymers 60 thatmay be utilized with and/or included in the systems and methodsaccording to the present disclosure include any suitable crosslinkedpolymer, polyactylate, polyacrylamide, acrylic-acrylamide copolymer,hydrolyzed cellulose-polyacrylonitrile, starch-polyacrylonitrile graftcopolymer, maleic anhydride copolymer, ethylenically derived monomomer,ethylenically unsaturated monomer, acrylate, anionic polyacrylamide,sodium polyacrylate, polyacrylamide copolymer, ethylene maleic anhydridecopolymer, carboxymethylcellulose, polyvinyl alcohol copolymer,polyethylene oxide, synthetic hydrophilic polymer, naturally occurringhydrophilic polymer, water insoluble polymer, silica gel, and/oraerogel. Additional illustrative, non-exclusive examples ofwater-absorbing polymer 60 include any suitable non-crosslinked polymer,powdered desiccant, biodegradable material, and/or non-biodegradablematerial.

Water-absorbing polymer 60 may comprise a plurality of water-absorbingpolymer particles, such as a powder, a dry powder, and/or a granularmaterial, that may define a polymer particle size distribution. This mayinclude any suitable single mode, bimodal, and/or multimodal particlesize distribution. In addition, the plurality of water-absorbing polymerparticles may define any suitable average, mean, and/or mediancharacteristic dimension, such as a size, diameter, and/or effectivediameter. As illustrative, non-exclusive examples, the characteristicdimension may be at least 1 micrometer (um), at least 5 um, at least 10um, at least 50 um, at least 100 um, at least 500 um, at least 1,000 um,or at least 5,000 um. Additionally or alternatively, the characteristicdimension also may be less than 20,000 um, less than 15,000 um, lessthan 10,000 um, less than 7,500 um, less than 5,000 um, less than 2,500um, or less than 1,000 um.

It is within the scope of the present disclosure that encapsulatedwater-absorbing polymer 65, when utilized, may include any of thewater-absorbing polymers 60 that are described herein (beneath/withincoating material 64). It is also within the scope of the presentdisclosure that water-absorbing polymer 60 and/or encapsulatedwater-absorbing polymer 65 may be pure, may not be diluted, and/or maynot include carrier and/or filler materials prior to being combined withmine tailings slurry 40. As an illustrative, non-exclusive example, andwhen the water-absorbing polymer includes a plurality of water-absorbingpolymer particles, the plurality of water-absorbing polymer particlesmay be conveyed in dry, powdered, and/or granular form and/or may be dryimmediately prior to being mixed with mine tailings slurry 40.

However, it is also within the scope of the present disclosure thatwater-absorbing polymer 60 may include a fluid carrier 63 and that thewater-absorbing polymer may be suspended or otherwise entrained or mixedwithin the fluid carrier prior to being combined with mine tailingsslurry 40. Illustrative, non-exclusive examples of fluid carriers thatmay be utilized with the systems and methods according to the presentdisclosure include fluid carriers that are not absorbed bywater-absorbing polymer 60, fluid carriers within which thewater-absorbing polymer is not soluble or otherwise reactive ornegatively altered, and/or fluid carriers that do not degrade coatingmaterial 64 of encapsulated water-absorbing polymer 65. More specificbut still illustrative, non-exclusive examples of fluid carriers thatmay be utilized with the systems and methods according to the presentdisclosure include any suitable non-aqueous fluid, non-aqueous liquid,hydrocarbon fluid, hydrocarbon liquid, alcohol, and/or alkane.

Mixing vessel 50 and/or thickening assembly 52 may include a tank body53 that defines internal volume 51. The tank body further may define aflocculant inlet 59 to receive flocculant 58 into internal volume 51, awater-absorbing polymer inlet 61 to receive water-absorbing polymer 60into internal volume 51, and a mine tailings inlet 41 to receive minetailings slurry 40 into internal volume 51. The tank body also maydefine an overflow outlet 55 to produce overflow 54, or overflow stream54, from internal volume 51 and an underflow outlet 57 to produceunderflow 56, or underflow stream 56, from internal volume 51. Inaddition, mixing vessel 50 also may include, or define, a mixingstructure 74 that is configured to combine mine tailings slurry 40,flocculant 58, and water-absorbing polymer 60 within internal volume 51.Subsequently, these materials may be allowed to flocculate withininternal volume 51 for at least a threshold thickening time,illustrative, non-exclusive examples of which are disclosed herein,thereby producing overflow 54 and underflow 56.

FIG. 2 is a flowchart depicting methods 100 according to the presentdisclosure of dewatering mine tailings. Methods 100 may include defininga water-absorbing polymer at 110 and include combining a mine tailingsslurry with the water-absorbing polymer to generate an augmented minetailings slurry at 120. Methods 100 further include piping the augmentedmine tailings slurry through a transfer pipe to a mine tailingsdewatering site at 130 and distributing the augmented mine tailingsslurry within the mine tailings dewatering site to form a mine tailingsdeposit at 140. Methods 100 further may include waiting at least athreshold dewatering time at 150, initiating water absorption by thewater-absorbing polymer at 160, and performing one or more additionalmethod steps at 170.

Defining the water-absorbing polymer at 110 may include selecting,regulating, creating, synthesizing, and/or formulating thewater-absorbing polymer, or any component and/or property thereof, basedupon any suitable criteria. As an illustrative, non-exclusive example,the defining at 110 may include forming, or selecting, an encapsulatedwater-absorbing polymer that is encapsulated by a coating material. Thismay, but is not required to, include forming the encapsulatedwater-absorbing polymer using methods 300 that are discussed in moredetail herein.

As another illustrative, non-exclusive example, and when the defining at110 includes forming the encapsulated water-absorbing polymer, thedefining at 110 further may include selecting at least one property ofthe coating material. The selecting may be based, at least in part, uponany suitable criteria, illustrative, non-exclusive examples of whichinclude a threshold thickening time for the augmented mine tailingsslurry, a threshold piping time for the augmented mine tailings slurry,a threshold distributing time for the augmented mine tailings slurry,and/or the threshold dewatering time. Illustrative, non-exclusiveexamples of these times are discussed in more detail herein.Illustrative, non-exclusive examples of properties of the coatingmaterial include a composition of the coating material, a thickness ofthe coating material, and/or the threshold isolation time that may beprovided by the coating material.

It is within the scope of the present disclosure that the coatingmaterial may include and/or be any suitable coating material and/or mayinclude and/or be defined by any suitable composition, or chemicalcomposition. As an illustrative, non-exclusive example, the coatingmaterial may include and/or be a water-soluble coating material. Asanother illustrative, non-exclusive example, the coating material mayinclude and/or be a starch.

As discussed, the water-absorbing polymer and/or the encapsulatedwater-absorbing polymer may be selected such that water absorption bythe water-absorbing polymer is initiated subsequent to deposition of theaugmented mine tailings slurry within the mine tailings dewatering site,subsequent to piping the augmented mine tailings slurry to the minetailings dewatering site, and/or subsequent to formation of the minetailings deposit within the mine tailings dewatering site. As such, itis within the scope of the present disclosure that, when thewater-absorbing polymer is encapsulated by the coating material, thecoating material may be selected to fluidly isolate the water-absorbingpolymer from water within the augmented mine tailings slurry for atleast the threshold isolation time.

Illustrative, non-exclusive examples of threshold isolation timesaccording to the present disclosure include threshold isolation times ofat least 0.5 hours, at least 0.75 hours, at least 1 hour, at least 2hours, at least 3 hours, at least 4 hours, at least 5 hours, at least 6hours, at least 8 hours, at least 10 hours, at least 12 hours, at least14 hours, at least 16 hours, at least 18 hours, at least 20 hours, or atleast 22 hours. Additionally or alternatively, the threshold isolationtime also may be less than 48 hours, less than 44 hours, less than 40hours, less than 36 hours, less than 32 hours, less than 28 hours, lessthan 24 hours, less than 22 hours, less than 20 hours, less than 18hours, less than 16 hours, less than 14 hours, less than 12 hours, orless than 10 hours.

As yet another illustrative, non-exclusive example, the mine tailingsslurry may include a plurality of tailings particles, such as aplurality of clay particles, that may define a plurality of tailingsparticle sizes. In addition, the water-absorbing polymer may define aplurality of water-absorbing polymer particles that define a pluralityof pores. Under these conditions, the defining at 110 also may includeselecting a crosslinking density of the water-absorbing polymer suchthat the water-absorbing polymer defines a pore size, or an average poresize, that is greater than at least a portion of the plurality oftailings particle sizes. This may permit a portion of the tailingsparticles to become entrained, entrapped, and/or otherwise enclosedwithin the plurality of pores, thereby changing an overall density ofthe water-absorbing polymer particles. As an illustrative, non-exclusiveexample, the entrained tailings particles may increase, or otherwiseadjust, the overall density of the water-absorbing polymer particlessuch that it is closer to the density of the tailings particles than acomparable polymer particle that does not include the entrained tailingsparticles. Adjusting the density of the water-absorbing polymerparticles may permit, or provide, an improved distribution of thewater-absorbing polymer (and/or encapsulated water-absorbing polymer)within the mine tailings slurry. Although not required, this in turn mayimprove the water-absorbing polymer's effectiveness to dewater theslurry and/or reduce the time required to remove sufficient amounts ofwater from the slurry.

As another illustrative, non-exclusive example, a water absorption rateof the water-absorbing polymer may be controlled, selected, and/or basedupon a particle size of the water-absorbing polymer particles that maybe defined by the water-absorbing polymer, with smaller water-absorbingpolymer particles absorbing water more quickly (or having a higher waterabsorption rate) than larger particles. Additionally or alternatively,the water absorption rate also may be controlled, selected, and/or basedupon a crosslinking density of the water-absorbing polymer, with lowercrosslinking densities absorbing water more quickly (or having a higherwater absorption rate) than higher crosslinking densities. Thus, thedefining at 110 also may include selecting an average polymer particlesize and/or an average crosslinking density based, at least in part, ona desired water absorption rate by the water-absorbing polymerparticles.

Additionally or alternatively, a particle size distribution of thewater-absorbing polymer particles may be selected such that a portion ofthe water-absorbing polymer particles absorb water at a water absorptionrate that is different from a remainder of the water-absorbing polymerparticles. Thus, the defining at 110 also may include selecting abimodal, or multimodal, particle size distribution that includes aplurality of subsets of water-absorbing polymer particles that absorbwater at different water absorption rates (or different average waterabsorption rates).

As yet another illustrative, non-exclusive example, some water-absorbingpolymers may crosslink, form a network, and/or form one or more fluidconduits within the augmented mine tailings slurry and/or the minetailings deposit. With this in mind, the defining at 110 also mayinclude selecting the water-absorbing polymer, or any suitable propertythereof, such that the water-absorbing polymer increases the fluidpermeability of the augmented mine tailings slurry and/or of the minetailings deposit by at least a threshold fluid permeability increase. Asillustrative, non-exclusive examples, the fluid permeability increasemay be at least 2 times, at least 3 times, at least 4 times, at least 5times, at least 6 times, at least 7 times, at least 8 times, at least 9times, or at least 10 times the fluid permeability of a comparable minetailings deposit that does not include the water-absorbing polymer.

As another illustrative, non-exclusive example, the defining at 110additionally or alternatively may include selecting and/or adjusting aconcentration of the water-absorbing polymer within the augmented minetailings slurry (or within the mine tailings that are present therein)based upon one or more properties of the mine tailings slurry and/orbased upon one or more properties of the augmented mine tailings slurry.As illustrative, non-exclusive examples, the concentration may beselected and/or adjusted based, at least in part, on a property of themine tailings slurry prior to combination with the mass ofwater-absorbing polymer, a property the mine tailings slurry subsequentto combination with the mass of water-absorbing polymer, the weather, anambient temperature, a particle size distribution within the minetailings slurry, a clay content of the mine tailings slurry, a type ofclay within the mine tailings slurry, a turbidity of the mine tailingsslurry, and/or a desired shear strength of the mine tailings depositthat may be formed from the augmented mine tailings slurry.

Combining the mine tailings slurry with the water-absorbing polymer togenerate the augmented mine tailings slurry at 120 may include combiningand/or otherwise mixing the mine tailings slurry and the water-absorbingpolymer in any suitable manner and/or using any suitable structure. Thismay include actively and/or passively mixing the mine tailings slurryand the water-absorbing polymer, injecting the mine tailings slurry intothe water-absorbing polymer, and/or injecting the water-absorbingpolymer into the mine tailings slurry. As discussed, the mine tailingsslurry may include mine tailings and water. As also discussed, thewater-absorbing polymer may include, be, and/or form a portion of anencapsulated water-absorbing polymer.

As an illustrative, non-exclusive example, the combining at 120 mayinclude combining within a thickening assembly at 122. Illustrative,non-exclusive examples of thickening assemblies are discussed herein.When the combining at 120 includes combining within the thickeningassembly, methods 100 further may include combining both the minetailings slurry and the water-absorbing polymer with a flocculant withinthe thickening assembly to generate the augmented mine tailings slurry.

It is within the scope of the present disclosure that methods 100further may include retaining the augmented mine tailings slurry withinthe thickening assembly for at least a threshold thickening timesubsequent to the combining at 122 and prior to the piping at 130.Illustrative, non-exclusive examples of threshold thickening timesaccording to the present disclosure include threshold thickening timesof at least 15 minutes, at least 30 minutes, at least 45 minutes, atleast 1 hour, at least 1.5 hours, at least 2 hours, at least 2.5 hours,at least 3 hours, at least 3.5 hours, or at least 4 hours.

During the threshold thickening time, the flocculant may cause at leasta portion of the tailings particles within the mine tailings slurry toflocculate. Subsequently, at least a portion of the flocculated minetailings, together with a portion of the water and at least a portion ofthe water-absorbing polymer may be produced from the thickening assemblyas an underflow, which also may be referred to herein as an underflowstream and/or as the augmented mine tailings slurry. In addition, thethickening assembly also may produce an overflow, which also may bereferred to herein as an overflow stream, and a solids content of theunderflow may be greater than a solids content of the overflow.

When the combining at 120 includes combining within the thickeningassembly at 122, it is within the scope of the present disclosure thatthe thickening assembly may be located at least a threshold pipingdistance from the mine tailings dewatering site and that the piping at130 may include piping the augmented mine tailings slurry through thetransfer pipe and over and/or across at least the threshold pipingdistance. Illustrative, non-exclusive examples of threshold pipingdistances according to the present disclosure include threshold pipingdistances of at least 100 meters (m), at least 200 m, at least 400 m, atleast 600 m, at least 800 m, at least 1,000 m, at least 1,250 m, atleast 1,500 m, at least 1,750 m, at least 2,000 m, at least 2,500 m, atleast 3,000 m, at least 3,500 m, at least 4,000 m, at least 4,500 m, atleast 5,000 m, at least 5,500 m, or at least 6,000 m. Additionalillustrative, non-exclusive examples of threshold piping distancesinclude distances that are less than 2,500 m, less than 2,000 m, lessthan 1,500 m, less than 1,000 m, or less than 500 m.

As another illustrative, non-exclusive example, the combining at 120also may include combining within the transfer pipe, as indicated at124. As an illustrative, non-exclusive example, and as discussed, thetransfer pipe may include an injection port, and the combining at 124may include injecting the water-absorbing polymer into the injectionport. When methods 100 include the combining at 124, it is within thescope of the present disclosure that the injection port may be locatedless than a threshold injection port distance from the mine tailingsdewatering site and that the piping at 130 may include piping theaugmented mine tailings slurry over and/or across the thresholdinjection port distance. Illustrative, non-exclusive examples ofthreshold injection port distances according to the present disclosureinclude threshold injection port distances of less than 200 meters, lessthan 150 meters, less than 125 meters, less than 100 meters, less than90 meters, less than 80 meters, less than 70 meters, less than 60meters, less than 50 meters, less than 40 meters, less than 30 meters,less than 20 meters, less than 15 meters, less than 10 meters, less than5 meters, or less than 2.5 meters.

Additionally or alternatively, it is also within the scope of thepresent disclosure that the injection port may be associated with, near,and/or integrated into a pump that is configured to provide a motiveforce for the piping at 130. Under these conditions, the thresholdinjection port distance may be less than 3,000 m, less than 2,750 m,less than 2,500 m, less than 2,250 m, less than 2,000 m, less than 1,750m, less than 1,500 m, less than 1,250 m, or less than 1,000 m.Additionally or alternatively, the threshold injection port distancealso may be greater than 500 m, greater than 1,000 m, greater than 1,500m greater than 2,000 m, or greater than 2,500 m.

Piping the augmented mine tailings slurry to the mine tailingsdewatering site at 130 may include piping the augmented mine tailingsslurry through the transfer pipe. This may include pumping,transporting, and/or otherwise conveying the augmented mine tailingsslurry over any suitable piping distance, illustrative, non-exclusiveexamples of which are disclosed herein. Additionally or alternatively,the piping at 130 also may include piping for at least a thresholdpiping time. Illustrative, non-exclusive examples of threshold pipingtimes according to the present disclosure include threshold piping timesof at least 5 minutes, at least 10 minutes, at least 15 minutes, atleast 20 minutes, at least 25 minutes, at least 30 minutes, at least 35minutes, at least 40 minutes, at least 45 minutes, at least 50 minutes,or at least 55 minutes. Additional illustrative, non-exclusive examplesof threshold piping times according to the present disclosure includethreshold piping times of less than 120 minutes, less than 110 minutes,less than 100 minutes, less than 90 minutes, less than 80 minutes, lessthan 70 minutes, or less than 60 minutes.

Distributing the augmented mine tailings slurry within the mine tailingsdewatering site to form the mine tailings deposit at 140 may includedistributing the augmented mine tailings slurry in any suitable manner.As illustrative, non-exclusive examples, the distributing at 140 mayinclude flowing the augmented mine tailings slurry within the minetailings dewatering site, flowing the augmented mine tailings slurrydown a sloped surface that is present within and/or defines the minetailings dewatering site, spraying the augmented mine tailings slurryinto the mine tailings dewatering site, and/or broadcasting theaugmented mine tailings slurry into the mine tailings dewatering site.

When the distributing at 140 includes flowing the augmented minetailings slurry down the sloped surface, the sloped surface may define asurface grade of at least 0.25%, at least 0.5%, at least 0.75%, at least1%, at least 1.5%, at least 2%, at least 2.5%, or at least 3%.Additionally or alternatively, the sloped surface also may define asurface grade of less than 7%, less than 6.5%, less than 6%, less than5.5%, less than 5%, less than 4.5%, less than 4%, less than 3.5%, orless than 3%.

It is within the scope of the present disclosure that the distributingat 140 may include distributing a given volume of mine tailings for atleast a threshold distributing time and/or that, subsequent to thepiping at 130, the given volume of the augmented mine tailings slurrymay move, settle, flow, and/or expand within the mine tailingsdewatering site for at least the threshold distributing time.Illustrative, non-exclusive examples of threshold distributing timesaccording to the present disclosure include threshold distributing timesof at least 0.5 hours, at least 0.75 hours, at least 1 hour, at least1.25 hours, at least 1.5 hours, at least 1.75 hours, at least 2 hours,at least 2.25 hours, at least 2.5 hours, at least 2.75 hours, at least 3hours, at least 3.25 hours, or at least 3.5 hours. Additionalillustrative, non-exclusive examples of threshold distributing timesaccording to the present disclosure include threshold distributing timesof less than 8 hours, less than 7 hours, less than 6 hours, less than 5hours, less than 4.75 hours, less than 4.5 hours, less than 4.25 hours,or less than 4 hours.

Optionally waiting at least the threshold dewatering time at 150 mayinclude waiting at least the threshold dewatering time subsequent to thedistributing at 140 and prior to the initiating at 160. As anillustrative, non-exclusive example, the waiting at 150 may permit waterthat may be present within the augmented mine tailings slurry, and whichwill naturally separate from a remainder of the augmented mine tailingsslurry on a time scale that is comparable to, or less than, thethreshold dewatering time, to separate and/or flow away from theremainder of the augmented mine tailings slurry prior to absorption ofwater by the water-absorbing polymer (such as during the initiating at160). Thus, the waiting at 150 may permit a lower concentration, ormass, of water-absorbing polymer to dewater a given mass of the minetailings slurry.

Illustrative, non-exclusive examples of threshold dewatering timesaccording to the present disclosure include threshold dewatering timesof at least 0.5 hours, at least 0.75 hours, at least 1 hour, at least 2hours, at least 3 hours, at least 4 hours, at least 5 hours, at least 6hours, at least 8 hours, at least 10 hours, at least 12 hours, at least14 hours, at least 16 hours, at least 18 hours, at least 20 hours, or atleast 22 hours. Additional illustrative, non-exclusive examples ofthreshold dewatering times according to the present disclosure includethreshold dewatering times of less than 48 hours, less than 44 hours,less than 40 hours, less than 36 hours, less than 32 hours, less than 28hours, less than 24 hours, less than 22 hours, less than 20 hours, lessthan 18 hours, less than 16 hours, less than 14 hours, less than 12hours, or less than 10 hours.

Initiating water absorption by the water-absorbing polymer at 160 mayinclude degrading the coating material to permit water absorption by thewater-absorbing polymer. It is within the scope of the presentdisclosure that the degrading may be accomplished in any suitablefashion. As an illustrative, non-exclusive example, the degrading mayinclude dissolving the coating material within the water that is presentwithin the augmented mine tailings slurry. As another illustrative,non-exclusive example, the degrading may include oxidizing the coatingmaterial. As yet another illustrative, non-exclusive example, thedegrading may be initiated responsive to fluid contact between thecoating material and water. As another illustrative, non-exclusiveexample, the degrading may be initiated responsive to a decrease in atemperature of the coating material (such as when the augmented minetailings slurry is produced during the combining at 120 at an elevatedtemperature and cools during the piping at 130, the distributing at 140,and/or the waiting at 160). Additionally or alternatively, it is alsowithin the scope of the present disclosure that the degrading may not beresponsive to, or at least may not be directly, or primarily, responsiveto abrasion of the coating material (such as during the piping at 130and/or during the distributing at 140).

Regardless of the specific mechanism that may be utilized to accomplishthe initiating at 130, it is within the scope of the present disclosurethat the initiating may be subsequent to the piping at 130, subsequentto the distributing at 140, and/or subsequent to the waiting at 150. Asan illustrative, non-exclusive example, and as discussed, the combiningat 120 may include combining the mine tailings slurry with thewater-absorbing polymer prior to piping the augmented mine tailingsslurry to the mine tailings dewatering site (at 130), distributing theaugmented mine tailings slurry within the mine tailings dewatering site(at 140), and/or waiting the threshold dewatering time (at 150). Assuch, and should the water-absorbing polymer begin absorbing water fromthe augmented mine tailings slurry prior to the initiating at 150, aviscosity and/or shear strength of the augmented mine tailings slurrywould increase, potentially dramatically. This would increase aresistance to flow and/or motion of the augmented mine tailings slurry,thereby increasing an expense of the piping at 130 and/or precluding thepiping at 130 as a means of transferring the water-absorbing polymer.Thus, selection of the water-absorbing polymer and/or the coatingmaterial such that the water absorption by the water-absorbing polymeris initiated subsequent to the piping at 130, the distributing at 140,and/or the waiting at 150 may permit the piping at 130 and/or thedistributing at 140, increasing an overall efficiency of methods 100and/or enabling methods 100 to be performed.

Performing one or more additional method steps at 170 may includeperforming any suitable additional method steps prior to, during, and/orsubsequent to performing a remainder of methods 100. As an illustrative,non-exclusive example, and subsequent to at least the distributing at140, the performing at 170 may include incorporating an additional massof water-absorbing polymer into the mine tailings deposit using methods200, which are discussed herein. This may include incorporating anadditional mass of water-absorbing polymer that is (compositionally) thesame as, or at least similar to, the mass of water-absorbing polymerthat was combined with the mine tailings slurry during the combining at120 and/or incorporating an additional mass of water-absorbing polymerthat is (compositionally) different from the mass of water-absorbingpolymer that was combined with the mine tailings slurry during thecombining at 120. As an illustrative, non-exclusive example, and sincemethods 200 do not include the piping at 130, the additional mass ofwater-absorbing polymer may not include the coating material and/or maybegin to absorb water immediately upon contact therewith.

As another illustrative, non-exclusive example, and subsequent to theinitiating at 160, the performing at 170 also may include reclaiming,reusing, and/or recycling the water-absorbing polymer using methods 400,which are discussed herein. Under these conditions, the mine tailingsdisposal site of methods 100 may include and/or be a temporary minetailings storage site and/or may form a portion of and/or be associatedwith a separation assembly that may be utilized during methods 400.

As yet another illustrative, non-exclusive example, the performing at170 also may include combining the mine tailings slurry (or theaugmented mine tailings slurry) with an additional additive.Illustrative, non-exclusive examples of additional additives accordingto the present disclosure include a polymer flocculant, an anionicflocculant, a cationic flocculant, a divalent cationic flocculant, atrivalent cationic flocculant, a nonionic flocculant, a flocculant thatincludes magnesium, a flocculant that includes calcium, and/or anotherflocculant that may be utilized to further flocculate mine tailings fromthe mine tailings slurry. Additionally or alternatively, the additionaladditive also may include cement, a cementitious material, a flycompound, a coagulant, a desiccant, and/or Portland cement. Additionallyor alternatively, the additional additive also may include another, or asecond, water-absorbing polymer that is different from thewater-absorbing polymer that is combined with the mine tailings slurryduring the combining at 120. Additionally or alternatively, theadditional additive also may include a material that is selected toincrease a fluid permeability of the augmented mine tailings slurryand/or of the dewatered mine tailings slurry.

It is within the scope of the present disclosure that the mine tailingsslurry may include and/or be a colloidal suspension and that changingthe pH of the mine tailings slurry may decrease a stability of thecolloidal suspension and/or generate separation of solids that may bepresent within the colloidal suspension from the water that is presentwithin the colloidal suspension. Thus, an additional illustrative,non-exclusive example of an additional additive according to the presentdisclosure includes a pH modifier, such as an acid and/or a base.

As an illustrative, non-exclusive example, and when the pH modifierincludes an acid, the performing at 170 may include decreasing the pH ofthe mine tailings slurry (or the augmented mine tailings slurry). Thismay include decreasing the pH to a pH that is less than 7.5, less than7.4, less than 7.3, less than 7.2, less than 7.1, less than 7.0, lessthan 6.9, less than 6.8, less than 6.7, less than 6.6, less than 6.5,less than 6.4, less than 6.3, less than 6.2, less than 6.1, less than6.0, less than 5.9, less than 5.8, less than 5.7, less than 5.6, or lessthan 5.5.

As another illustrative, non-exclusive example, and when the pH modifierincludes a base, the performing at 170 also may include increasing thepH of the mine tailings slurry (or the augmented mine tailings slurry).This may include increasing the pH to a pH that is at least 8.5, atleast 8.75, at least 9.0, at least 9.25, at least 9.5, at least 9.75, atleast 10, at least 10.1, at least 10.2, at least 10.3, at least 10.4, atleast 10.5, at least 10.6, at least 10.7, at least 10.8, at least 10.9,or at least 11.0.

It is within the scope of the present disclosure that the additionaladditive may be combined with the mine tailings slurry (or the augmentedmine tailings slurry) at any suitable time and/or at any suitable pointwithin methods 100. As an illustrative, non-exclusive example, theadditional additive may be combined with the mine tailings slurry priorto the combining at 120. As another illustrative, non-exclusive example,the additional additive may be combined with the augmented mine tailingsslurry subsequent to the combining at 120. As yet another illustrative,non-exclusive example, the additional additive may be combined with themine tailings slurry during, or concurrently with, the combining at 120.

As another illustrative, non-exclusive example, and subsequent to theinitiating at 160, the performing at 170 also may include crosslinkingthe water-absorbing polymer within the mine tailings slurry (or withinthe mine tailings deposit). It is within the scope of the presentdisclosure that the crosslinking may be responsive to the initiating at160. Additionally or alternatively, it is also within the scope of thepresent disclosure that methods 100 further may include supplying aninitiator to the mine tailings slurry and/or to the mine tailingsdeposit to initiate the crosslinking.

FIG. 3 is a flowchart depicting additional methods 200 according to thepresent disclosure of dewatering mine tailings. Methods 200 may includedefining a water-absorbing polymer at 210 (which may be at leastsubstantially similar to, or optionally even the same as, the definingat 110) and include distributing a mine tailings slurry, which includesmine tailings and water, within a mine tailings dewatering site to forma mine tailings deposit at 220. Methods 200 further may include waitingat least a threshold settling time at 230 and distributing a mass ofwater-absorbing polymer within the mine tailings dewatering site at 240.Methods 200 further include mechanically incorporating the mass ofwater-absorbing polymer into the mine tailings deposit at 250, andmethods 200 may include performing one or more additional steps at 260.

Distributing the mine tailings slurry within the mine tailingsdewatering site at 220 may include distributing the mine tailings slurryin any suitable manner. It is within the scope of the present disclosurethat the distributing the mine tailings slurry at 220 may be similar to,at least substantially similar to, or even the same as, the distributingthe augmented mine tailings slurry at 140, which is discussed in moredetail herein with reference to methods 100.

Waiting at least the threshold settling time at 230 may include waitingany suitable settling time subsequent to the distributing at 220 andprior to the mechanically incorporating at 250. As an illustrative,non-exclusive example, and as discussed, the mechanically incorporatingat 250 may include mechanically incorporating using one or moremechanical incorporation devices. The mechanical incorporation devicemay be configured to drive, or be driven or otherwise conveyed, acrossan upper surface of the mine tailings deposit. However, immediatelysubsequent to the distributing at 220, a shear strength of the minetailings deposit may be insufficient to support the mechanicalincorporation device and/or to permit the mechanical incorporationdevice to drive thereacross. As such, the waiting at 230 may permit themechanically incorporating at 230.

As another illustrative, non-exclusive example, and as also discussed, aportion of the water that is contained within the mine tailings slurrymay separate from the mine tailings slurry naturally during the waitingat 230. Thus, the waiting at 230 may permit dewatering of the minetailings slurry using a smaller mass of water-absorbing polymer thanwhat might be needed in a comparable method that does not include thewaiting at 230. Illustrative, non-exclusive examples of thresholdsettling times according to the present disclosure include thresholdsettling times of at least 1 hour, at least 2 hours, at least 4 hours,at least 8 hours, at least 12 hours, at least 18 hours, at least 1 day,at least 1.5 days, at least 2 days, at least 3 days, at least 4 days, atleast 5 days, at least 6 days, at least 7 days, at least 8 days, atleast 9 days, or at least 10 days. Additional illustrative,non-exclusive examples of threshold setting times include times that aregreater than 1 day and less than 1 month, greater than 1 day and lessthan 3 weeks, greater than 3 days and less than 2 weeks, greater than 4days and less than 10 days, or greater than 6 days and less than 9 days.

Distributing the mass of water-absorbing polymer within the minetailings dewatering site at 240 may include distributing the mass ofwater-absorbing polymer subsequent to the distributing at 220 and/orprior to the mechanically incorporating at 250. As an illustrative,non-exclusive example, and as discussed, the mass of water-absorbingpolymer may include a dry powder and/or a dry particulate. Thus, thedistributing at 240 may include broadcasting, dropping, and/or spreadingthe mass of water-absorbing polymer onto the mine tailings deposit (oran upper surface thereof). As another illustrative, non-exclusiveexample, and as also discussed, the water-absorbing polymer may besuspended in a fluid carrier to form a polymer suspension. Thus, thedistributing at 240 may include spraying and/or flowing the mass ofwater-absorbing polymer onto the mine tailings deposit (or an uppersurface thereof).

Mechanically incorporating the mass of water-absorbing polymer into themine tailings deposit at 250 may include mechanically incorporating, ormixing, the mass of water-absorbing polymer into the mine tailingsdeposit in any suitable manner. As an illustrative, non-exclusiveexample, and as discussed, the mechanically incorporating may includemechanically incorporating with a mechanical incorporation device,illustrative, non-exclusive examples of which are discussed herein. Asanother illustrative, non-exclusive example, the mechanicallyincorporating may include mud farming. As additional illustrative,non-exclusive examples, the mechanically incorporating also may includeagitating the mine tailings deposit, disking the mine tailings deposit,tilling the mine tailings deposit, rototilling the mine tailingsdeposit, and/or turning the mine tailings deposit.

Performing one or more additional steps at 260 may include performingany suitable additional method steps prior to, during, and/or subsequentto performing a remainder of methods 200. As an illustrative,non-exclusive example, the performing at 260 may include reclaiming,reusing, and/or recycling the water-absorbing polymer using methods 400,which are discussed herein. Under these conditions, the mine tailingsdisposal site of methods 200 may include and/or be a temporary minetailings disposal site and/or may form a portion of and/or may beassociated with a separation assembly that may be utilized duringmethods 400.

As another illustrative, non-exclusive example, the performing at 260also may include adding one or more additional additives to the minetailings slurry and/or to the mine tailings deposit. This may includeadding the one or more additional additives prior to the distributing at220, concurrently with the distributing at 220, subsequent to thedistributing at 220, prior to the distributing at 240, concurrently withthe distributing at 240, subsequent to the distributing at 240, prior tothe mechanically incorporating at 250, concurrently with themechanically incorporating at 250, and/or subsequent to the mechanicallyincorporating at 250. Illustrative, non-exclusive examples of additionaladditives according to the present disclosure are discussed in moredetail herein. As yet another illustrative, non-exclusive example, theperforming at 260 also may include crosslinking the water-absorbingpolymer within the mine tailings deposit, which is also discussed inmore detail herein.

FIG. 4 is a flowchart depicting methods 300 according to the presentdisclosure of forming an encapsulated water-absorbing polymer that maybe utilized to dewater a mine tailings slurry that includes minetailings and water. Methods 300 may include determining a density of themine tailings at 310 and/or determining a density of a water-absorbingpolymer at 320. Methods 300 include selecting a coating material that isconfigured to encapsulate the water-absorbing polymer to form theencapsulated water-absorbing polymer at 330, selecting a thickness forthe coating material within the encapsulated water-absorbing polymer at340, and encapsulating the water-absorbing polymer in the coatingmaterial to form the encapsulated water-absorbing polymer at 350.

Determining the density of the mine tailings at 310 and/or determiningthe density of the water-absorbing polymer at 320 may includedetermining the density in any suitable manner. As illustrative,non-exclusive examples, the determining at 310 may include measuring thedensity of the mine tailings, obtaining the density of the mine tailings(such as from any suitable tabulation of mine tailings densities) and/orreceiving the density of the mine tailings from any suitable informationsource. As additional illustrative, non-exclusive examples, thedetermining at 320 may include measuring the density of thewater-absorbing polymer, obtaining the density of the water-absorbingpolymer (such as from a tabulation of water-absorbing polymersdensities) and/or receiving the density of the water-absorbing polymerfrom any suitable information source.

Selecting the coating material at 330 may include selecting any suitablecoating material, illustrative, non-exclusive examples of which arediscussed herein. As illustrative, non-exclusive examples, the selectingat 330 may include selecting a water-soluble coating material and/orselecting a coating material that will degrade after, during, and/orresponsive to contact with water. This may include selecting the coatingmaterial to degrade subsequent to contact with water for at least athreshold isolation time, illustrative, non-exclusive examples of whichare discussed herein. As another illustrative, non-exclusive example,the selecting at 330 may include selecting the coating material based,at least in part, on the density of the coating material and/or thedensity of the mine tailings. This may permit matching of a density ofthe encapsulated water-absorbing polymer to the density of the minetailings, as discussed herein with reference to the encapsulating at350.

Selecting the thickness for the coating material at 340 may includeselecting any suitable thickness for the coating material based upon anysuitable criteria. As an illustrative, non-exclusive example, thecoating material may degrade upon contact with water at a coatingmaterial degradation rate, and the selecting at 340 may includeselecting such that, subsequent to contact between the encapsulatedwater-absorbing polymer and water, the coating material fluidly isolatesthe water-absorbing polymer from the water for at least the thresholdisolation time. As another illustrative, non-exclusive example, theselecting at 340 may include selecting the thickness for the coatingmaterial based, at least in part, on the density of the coating materialand/or the density of the mine tailings slurry. This may permit matchingof the density of the encapsulated water-absorbing polymer to thedensity of the mine tailings, as discussed herein with reference to theencapsulating at 350.

Encapsulating the water-absorbing polymer in the coating material at 350may include coating, covering, surrounding, and/or encapsulating thewater-absorbing polymer in the coating material such that the coatingmaterial fluidly isolates the water-absorbing polymer, at leasttemporarily, from a fluid environment that surrounds the water-absorbingpolymer. This may include encapsulating the water-absorbing polymer withthe coating material that was selected during the selecting at 330 anddefining a thickness, or average thickness, of the coating material thatis based upon the thickness that was selected at 340. As anillustrative, non-exclusive example, the encapsulating at 350 mayinclude encapsulating such that, subsequent to fluid contact between theencapsulated water-absorbing polymer and water, the coating materialfluidly isolates the water-absorbing polymer from the water for at leastthe threshold isolation time.

As another illustrative, non-exclusive example, methods 300 may includeperforming the selecting at 330, the selecting at 340, and/or theencapsulating at 350 such that a ratio of the density of theencapsulated water-absorbing polymer to the density of the mine tailingsslurry is less than a threshold value. Illustrative, non-exclusiveexamples of threshold values according to the present disclosure, whichalso may be referred to herein as a threshold density ratios, includethreshold values of less than 1.25, less than 1.2, less than 1.15, lessthan 1.1, less than 1.08, less than 1.06, less than 1.04, or less than1.02. Additionally or alternatively, the threshold value also may begreater than 0.75, greater than 0.80, greater than 0.85, greater than0.90, greater than 0.92, greater than 0.94, greater than 0.96, orgreater than 0.98.

FIG. 5 is a flowchart depicting methods 400 according to the presentdisclosure of reclaiming, reusing, and/or recycling a water-absorbingpolymer. Methods 400 include absorbing, at 410, water from a minetailings slurry with a mass of water-absorbing polymer that is presentwithin and/or mixed with the mine tailings slurry to generate a mass ofswollen water-absorbing polymer and a dewatered mine tailings slurry.Methods 400 further include separating the mass of swollenwater-absorbing polymer from the dewatered mine tailings slurry at 420.Methods 400 further may include transporting the dewatered mine tailingsslurry to a mine tailings disposal site at 430, dewatering the swollenwater-absorbing polymer to produce a mass of regenerated water-absorbingpolymer and released water at 440, reusing the regeneratedwater-absorbing polymer at 450, and/or recycling the released water at460.

Absorbing water from the mine tailings with the mass of water-absorbingpolymer at 410 may include absorbing the water with any suitablewater-absorbing polymer, illustrative, non-exclusive examples of whichare discussed herein. This may include absorbing, or initiating theabsorbing, immediately, or at least substantially immediately,subsequent to contact between the water-absorbing polymer and the water.Additionally or alternatively, the absorbing at 410 also may includeabsorbing subsequent to at least a threshold isolation time, such aswhen the water-absorbing polymer is an encapsulated water-absorbingpolymer and/or includes a coating material. Illustrative, non-exclusiveexamples of threshold isolation times, coating materials, andencapsulated water-absorbing polymers are discussed in more detailherein.

Separating the mass of swollen water-absorbing polymer from the minetailings at 420 may include separating the mass of water-absorbingpolymer subsequent to the absorbing at 410 and may be based upon anysuitable quality, or property, of the water-absorbing polymer, theswollen water-absorbing polymer, and/or the mine tailings. As anillustrative, non-exclusive example, the separating at 420 may includeseparating based, at least in part, on a density difference between themass of swollen water-absorbing polymer and the dewatered mine tailingsslurry. As another illustrative, non-exclusive example, the separatingat 420 may include separating based, at least in part, on a sizedifference between the mass of swollen water-absorbing polymer and thedewatered mine tailings slurry. As yet another illustrative,non-exclusive example, the separating at 420 may include separatingbased, at least in part, on a shape difference between the mass ofswollen water-absorbing polymer and the dewatered mine tailings slurry.

It is within the scope of the present disclosure that the separating at420 may be accomplished in any suitable manner. As illustrative,non-exclusive examples, the separating may include physically separatingthe mass of swollen water-absorbing polymer from the dewatered minetailings slurry, chemically separating the mass of swollenwater-absorbing polymer from the dewatered mine tailings slurry,separating the mass of swollen water-absorbing polymer from thedewatered mine tailings slurry by agitation, and/or separating the massof water-absorbing polymer from the dewatered mine tailings slurry byfiltration.

Transporting the dewatered mine tailings slurry to the mine tailingsdisposal site at 430 may include transporting the dewatered minetailings slurry in any suitable manner. As illustrative, non-exclusiveexamples, the transporting at 430 may include conveying and/or truckingthe dewatered mine tailings slurry. A viscosity and/or shear strength ofthe dewatered mine tailings slurry may be such that it may be difficultand/or costly to pump and/or pipe the dewatered mine tailings slurry tothe mine tailings disposal site. However, it is within the scope of thepresent disclosure that the transporting at 430 also may include pumpingand/or piping the dewatered mine tailings slurry to the mine tailingsdisposal site.

Dewatering the mass of swollen water-absorbing polymer at 440 mayinclude dewatering the mass of swollen water-absorbing polymersubsequent to the absorbing at 410 and/or subsequent to the separatingat 420. This may include dewatering to regenerate at least a portion ofthe mass of water-absorbing polymer and/or to produce the mass ofregenerated water-absorbing polymer. Additionally or alternatively, thedewatering at 440 also may include separating, or releasing, water fromthe swollen water-absorbing polymer to produce, or generate, releasedwater.

It is within the scope of the present disclosure that the dewatering at440 may be accomplished in any suitable manner. As illustrative,non-exclusive examples, the dewatering at 440 may include dewatering byapplication of an electric field to the mass of swollen water-absorbingpolymer, dewatering by application of pressure to the mass of swollenwater-absorbing polymer, dewatering by application of a shear stress tothe mass of swollen water-absorbing polymer, dewatering by centrifugingthe mass of swollen water-absorbing polymer, dewatering by grinding themass of swollen water-absorbing polymer, dewatering by heating the massof swollen water-absorbing polymer, dewatering by freezing the mass ofswollen water-absorbing polymer, and/or dewatering by decreasing ahumidity in a vicinity of the mass of swollen water-absorbing polymer.

Reusing the mass of regenerated water-absorbing polymer at 450 may besubsequent to the dewatering at 440 and may include reusing the mass ofregenerated water-absorbing polymer in any suitable manner. Asillustrative, non-exclusive examples, the reusing at 450 may includemixing and/or otherwise combining the mass of regeneratedwater-absorbing polymer with mine tailings (such as discussed hereinwith reference to methods 100 and/or methods 200), encapsulating themass of regenerated water-absorbing polymer with a coating material(such as discussed herein with reference to methods 300), and/orabsorbing water from a mine tailings slurry with the regenerated mass ofregenerated water-absorbing polymer (such as during the absorbing at410). As another illustrative, non-exclusive example, the reusing at 450also may include reconstituting, or controlling a size, shape, and/orsize distribution, of the regenerated water-absorbing polymer (and/or ofa plurality of regenerated water-absorbing polymer particles that may bedefined by the regenerated water-absorbing polymer).

Recycling the released water at 460 may include utilizing, or reusing,the released water in any suitable manner. As an illustrative,non-exclusive example, the recycling at 460 may include providing, orsupplying, the released water to a component of a mining operation thatis performing methods 400. As another more specific but stillillustrative, non-exclusive example, the recycling at 460 may includecombining the released water with bitumen ore to generate, or produce,the mine tailings stream.

In the present disclosure, several of the illustrative, non-exclusiveexamples have been discussed and/or presented in the context of flowdiagrams, or flow charts, in which the methods are shown and describedas a series of blocks, or steps. Unless specifically set forth in theaccompanying description, it is within the scope of the presentdisclosure that the order of the blocks may vary from the illustratedorder in the flow diagram, including with two or more of the blocks (orsteps) occurring in a different order and/or concurrently. It is alsowithin the scope of the present disclosure that the blocks, or steps,may be implemented as logic, which also may be described as implementingthe blocks, or steps, as logics. In some applications, the blocks, orsteps, may represent expressions and/or actions to be performed byfunctionally equivalent circuits or other logic devices. The illustratedblocks may, but are not required to, represent executable instructionsthat cause a computer, processor, and/or other logic device to respond,to perform an action, to change states, to generate an output ordisplay, and/or to make decisions.

As used herein, the term “and/or” placed between a first entity and asecond entity means one of (1) the first entity, (2) the second entity,and (3) the first entity and the second entity. Multiple entities listedwith “and/or” should be construed in the same manner, i.e., “one ormore” of the entities so conjoined. Other entities may optionally bepresent other than the entities specifically identified by the “and/or”clause, whether related or unrelated to those entities specificallyidentified. Thus, as a non-limiting example, a reference to “A and/orB,” when used in conjunction with open-ended language such as“comprising” may refer, in one embodiment, to A only (optionallyincluding entities other than B); in another embodiment, to B only(optionally including entities other than A); in yet another embodiment,to both A and B (optionally including other entities). These entitiesmay refer to elements, actions, structures, steps, operations, values,and the like.

As used herein, the phrase “at least one,” in reference to a list of oneor more entities should be understood to mean at least one entityselected from any one or more of the entity in the list of entities, butnot necessarily including at least one of each and every entityspecifically listed within the list of entities and not excluding anycombinations of entities in the list of entities. This definition alsoallows that entities may optionally be present other than the entitiesspecifically identified within the list of entities to which the phrase“at least one” refers, whether related or unrelated to those entitiesspecifically identified. Thus, as a non-limiting example, “at least oneof A and B” (or, equivalently, “at least one of A or B,” or,equivalently “at least one of A and/or B”) may refer, in one embodiment,to at least one, optionally including more than one, A, with no Bpresent (and optionally including entities other than B); in anotherembodiment, to at least one, optionally including more than one, B, withno A present (and optionally including entities other than A); in yetanother embodiment, to at least one, optionally including more than one,A, and at least one, optionally including more than one, B (andoptionally including other entities). In other words, the phrases “atleast one,” “one or more,” and “and/or” are open-ended expressions thatare both conjunctive and disjunctive in operation. For example, each ofthe expressions “at least one of A, B and C,” “at least one of A, B, orC,” “one or more of A, B, and C,” “one or more of A, B, or C” and “A, B,and/or C” may mean A alone, B alone, C alone, A and B together, A and Ctogether, B and C together, A, B and C together, and optionally any ofthe above in combination with at least one other entity.

In the event that any patents, patent applications, or other referencesare incorporated by reference herein and (1) define a term in a mannerthat is inconsistent with and/or (2) are otherwise inconsistent with,either the non-incorporated portion of the present disclosure or any ofthe other incorporated references, the non-incorporated portion of thepresent disclosure shall control, and the term or incorporateddisclosure therein shall only control with respect to the reference inwhich the term is defined and/or the incorporated disclosure was presentoriginally.

As used herein the terms “adapted” and “configured” mean that theelement, component, or other subject matter is designed and/or intendedto perform a given function. Thus, the use of the terms “adapted” and“configured” should not be construed to mean that a given element,component, or other subject matter is simply “capable of” performing agiven function but that the element, component, and/or other subjectmatter is specifically selected, created, implemented, utilized,programmed, and/or designed for the purpose of performing the function.It is also within the scope of the present disclosure that elements,components, and/or other recited subject matter that is recited as beingadapted to perform a particular function may additionally oralternatively be described as being configured to perform that function,and vice versa.

Illustrative, non-exclusive examples of systems and methods according tothe present disclosure are presented. It is within the scope of thepresent disclosure that an individual step of a method recited herein,may additionally or alternatively be referred to as a “step for”performing the recited action.

INDUSTRIAL APPLICABILITY

The systems and methods disclosed herein are applicable to the oil andgas industry.

It is believed that the disclosure set forth above encompasses multipledistinct inventions with independent utility. While each of theseinventions has been disclosed in its preferred form, the specificembodiments thereof as disclosed and illustrated herein are not to beconsidered in a limiting sense as numerous variations are possible. Thesubject matter of the inventions includes all novel and non-obviouscombinations and subcombinations of the various elements, features,functions and/or properties disclosed herein. Similarly, where theclaims recite “a” or “a first” element or the equivalent thereof, suchclaims should be understood to include incorporation of one or more suchelements, neither requiring nor excluding two or more such elements.

It is believed that the following claims particularly point out certaincombinations and subcombinations that are directed to one of thedisclosed inventions and are novel and non-obvious. Inventions embodiedin other combinations and subcombinations of features, functions,elements and/or properties may be claimed through amendment of thepresent claims or presentation of new claims in this or a relatedapplication. Such amended or new claims, whether they are directed to adifferent invention or directed to the same invention, whetherdifferent, broader, narrower, or equal in scope to the original claims,are also regarded as included within the subject matter of theinventions of the present disclosure.

1. A method of dewatering a mine tailings slurry, the method comprising:combining the mine tailings slurry, which includes mine tailings andwater, with a water-absorbing polymer, which is encapsulated in acoating material that inhibits water absorption thereby, to generate anaugmented mine tailings slurry; piping the augmented mine tailingsslurry through a transfer pipe to a mine tailings dewatering site;distributing the augmented mine tailings slurry within the mine tailingsdewatering site to form a mine tailings deposit; and initiating waterabsorption by a mass of water-absorbing polymer subsequent to thepiping, wherein the initiating includes degrading the coating materialto permit water absorption by the mass of water-absorbing polymer. 2.The method of claim 1, wherein the combining the mine tailings slurrywith the water-absorbing polymer includes combining within a thickeningassembly, and wherein the method further comprises combining aflocculant with the mine tailings slurry and the water-absorbing polymerwithin the thickening assembly to generate the augmented mine tailingsslurry.
 3. The method of claim 2, wherein the thickening assembly islocated at least a threshold piping distance of at least 100 m from themine tailings dewatering site, and further wherein the piping includespiping across the threshold piping distance.
 4. The method of claim 1,wherein the combining includes combining within the transfer pipe byinjecting the water-absorbing polymer into an injection port of thetransfer pipe.
 5. The method of claim 1, further comprising selecting atleast one property of the coating material based, at least in part, onat least one of a threshold thickening time, a threshold piping time, athreshold distributing time, and a threshold dewatering time.
 6. Themethod of claim 5, wherein the at least one property of the coatingmaterial includes at least one of a composition of the coating materialand a thickness of the coating material.
 7. The method of claim 1,wherein the coating material is selected to fluidly isolate thewater-absorbing polymer from the water for a threshold isolation time ofat least 0.5 hours and less than 48 hours.
 8. The method of claim 1,further comprising waiting for at least a threshold dewatering timesubsequent to the distributing and prior to the initiating, wherein thethreshold dewatering time is at least 0.5 hours and less than 48 hours.9. A method of dewatering a mine tailings slurry, the method comprising:distributing the mine tailings slurry, which includes mine tailings andwater, within a mine tailings dewatering site as a mine tailingsdeposit; and mechanically incorporating a mass of water-absorbingpolymer into the mine tailings deposit subsequent to the distributing togenerate an augmented mine tailings slurry.
 10. The method of claim 9,wherein the mechanically incorporating includes at least one ofagitating the mine tailings deposit, disking the mine tailings deposit,tilling the mine tailings deposit, rototilling the mine tailingsdeposit, and turning the mine tailings deposit.
 11. The method claim 9,wherein, subsequent to the distributing the mine tailings slurry andprior to the mechanically incorporating the mass of water-absorbingpolymer, the method further comprises distributing the mass ofwater-absorbing polymer within the mine tailings dewatering site. 12.The method of claim 9, further comprising waiting at least a thresholdsettling time of at least 1 hour subsequent to the distributing the minetailings slurry and prior to the mechanically incorporating the mass ofwater-absorbing polymer.
 13. The method of claim 9, further comprising:absorbing water from the augmented mine tailings slurry with the mass ofwater-absorbing polymer to dewater the augmented mine tailings slurryand generate a mass of swollen water-absorbing polymer and a dewateredmine tailings slurry; and separating the mass of swollen water-absorbingpolymer from the dewatered mine tailings slurry subsequent to theabsorbing.
 14. The method of claim 13, wherein, subsequent to theseparating, the method further comprises transporting the dewatered minetailings slurry to a mine tailings disposal site.
 15. The method ofclaim 14, wherein, subsequent to the separating, the method furthercomprises dewatering the mass of swollen water-absorbing polymer toproduce a mass of regenerated water-absorbing polymer.
 16. The method ofclaim 15, wherein, subsequent to the dewatering the mass of swollenwater-absorbing polymer, the method further comprises reusing the massof regenerated water-absorbing polymer, and further wherein the reusingincludes combining the mass of regenerated water-absorbing polymer withthe mine tailings slurry and absorbing water from the mine tailingsslurry with the mass of regenerated water-absorbing polymer.
 17. Themethod of claim 9, further comprising adjusting a concentration of thewater-absorbing polymer within the augmented mine tailings slurry basedupon at least one of a property of the mine tailings slurry prior tocombination with the mass of water-absorbing polymer, a property theaugmented mine tailings slurry, weather, an ambient temperature, aparticle size distribution within the mine tailings slurry, a claycontent of the mine tailings slurry, a type of clay within the minetailings slurry, a turbidity of the mine tailings slurry, and a desiredshear strength of the mine tailings deposit.
 18. The method of claim 9,wherein the mine tailings slurry includes at least one of oil sandstailings, thickened tailings (TT), mature fine tailings (MFT), solventrecovery unit tailings (TSRU), and fluid fine tailings (FFT).
 19. Themethod of claim 9, wherein the mine tailings slurry includes at least0.05 wt % and less than 15 wt % bitumen.
 20. A method of forming anencapsulated water-absorbing polymer to be utilized to dewater a minetailings slurry that includes mine tailings and water, the methodcomprising: selecting a coating material that is configured toencapsulate a water-absorbing polymer to form the encapsulatedwater-absorbing polymer; selecting a thickness for the coating materialwithin the encapsulated water-absorbing polymer, wherein at least one ofthe selecting the coating material and the selecting the thickness isbased, at least in part, on a density of the mine tailings slurry and adensity of the water-absorbing polymer; and encapsulating thewater-absorbing polymer with the thickness of the coating material toform the encapsulated water-absorbing polymer, wherein a ratio of adensity of the encapsulated water-absorbing polymer to the density ofthe mine tailings slurry is less than a threshold value.
 21. The methodof claim 20, wherein the threshold value is less than 1.25 and greaterthan 0.75.
 22. The method of claim 21, wherein the water-absorbingpolymer defines a plurality of water-absorbing polymer particles thatdefine an average polymer particle size, and further wherein the methodincludes selecting the average polymer particle size based, at least inpart, on a desired water absorption rate by the plurality ofwater-absorbing polymer particles.
 23. The method of claim 21, whereinthe water-absorbing polymer defines a plurality of water-absorbingpolymer particles that define a particle size distribution, and whereinthe method further comprises selecting the particle size distributionbased, at least in part, on a desired water absorption rate by theplurality of water-absorbing polymer particles.
 24. The method of claim23, wherein the selecting the particle size distribution includesselecting a multimodal particle size distribution such that thewater-absorbing polymer particles that define a first mode of themultimodal particle size distribution absorb water at a first absorptionrate that is different from a second absorption rate of thewater-absorbing polymer particles that define a second mode of themultimodal particle size distribution.
 25. An apparatus for flocculatingand dewatering a mine tailings slurry, the apparatus comprising: a tankbody that defines: an internal volume; a flocculant inlet for providinga flocculant to the internal volume; a water-absorbing polymer inlet forproviding a water-absorbing polymer to the internal volume; a minetailings inlet for providing the mine tailings slurry to the internalvolume; an underflow outlet for removing an underflow from the internalvolume; and an overflow outlet for removing an overflow from theinternal volume; a mine tailings supply system that is configured toprovide the mine tailings slurry, which includes mine tailings andwater, to the mine tailings inlet; a flocculant supply system that isconfigured to provide the flocculant to the flocculant inlet; awater-absorbing polymer supply system that is configured to provide thewater-absorbing polymer to the water-absorbing polymer inlet; and amixing structure that is configured to combine the mine tailings slurry,the flocculant, and the water-absorbing polymer within the internalvolume of the tank body to generate the underflow, which is dischargedfrom the underflow outlet, and the overflow, which is discharged fromthe overflow outlet.
 26. The apparatus of claim 25, further comprisingthe water-absorbing polymer, and wherein at least a portion of thewater-absorbing polymer is located within the internal volume of thetank body.